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71.
Quantifying geological structures of the Nigde province in central Anatolia,Turkey using SRTM DEM data 总被引:1,自引:0,他引:1
A. C. Demirkesen 《Environmental Geology》2009,56(5):865-875
A digital terrain model and a 3D fly-through model of the Nigde province in central Anatolia, Turkey were generated and quantitatively
analyzed employing the shuttle radar topographic mission (SRTM) digital elevation model (DEM). Besides, stream drainage patterns,
lineaments and structural–geological features were extracted and analyzed. In the process of analyzing and interpreting the
DEM for landforms, criteria such as color and color tones (attributes of heights), topography (shaded DEM and 3D fly-through
model) and stream drainage patterns were employed to acquire geo-information about the land, such as hydrologic, geomorphologic,
topographic and tectonic structures. In this study, the SRTM DEM data of the study region were experimentally used for both
DEM classification and quantitative analysis of the digital terrain model. The results of the DEM classification are: (1)
low plain including the plains of Bor and Altunhisar (20.7%); (2) high plain including the Misli (Konakli) plain (28.8%);
(3) plateau plain including the Melendiz (Ciftlik) plateau plain (1.0%); (4) mountain including the Nigde massif (33.3%);
and (5) high mountain (16.2%). High mountain areas include a caldera complex of Mt Melendiz, Mt Hasan and Mt Pozanti apart
from the Ala mountains called Aladaglar and the Bolkar mountains called Bolkarlar in the study region (7,312 km2). Analysis of both the stream drainage patterns and the lineaments revealed that the Nigde province has a valley zone called
Karasu valley zone (KVZ) or Nigde valley zone (NVZ), where settlements and agricultural plains, particularly the Bor plain
in addition to settlements of the Bor town and the central city of Nigde have the most flooding risk when a heavy raining
occurs. The study revealed that the NVZ diagonally divides the study region roughly into two equal parts, heading from northeast
to southwest. According to the map created in this study, the right side of the NVZ has more mountainous area, where the Aladaglar
is a wildlife national park consisting of many species of fauna and flora whereas the left side of the NVZ has more agricultural
plain, with exception of a caldera complex of Mt Melendiz and volcanic Mt Hasan. The south of the study region includes the
Bolkarlar. In addition, the Ecemis fault zone (EFZ) lying along the Ecemis rivulet, running from north to south at the west
side of the Aladaglar, forms the most important and sensitive location in the region in terms of the tectonics. 相似文献
72.
This investigation had the purpose of evaluating the reliability of a sequential extraction procedure according to Zeien and Brümmer (1989) which is performed routinely to analyse the distribution of heavy metals to different soil phases. Reliability was tested by two hypotheses. According to the first hypothesis an error propagation increased during a morefold extraction of heavy metals from a single soil sample to such an extend that it does not allow a statistical comparison of different analyses. This assumption was confirmed in an interlaboratory study of five participants applying the sequential extraction scheme on two different soils. The heavy metal amounts extracted by the different partners were of the same magnitude, but from the results no statistical correspondence at the 95% confidence level could be observed. The second hypothesis stated that also weak extraction agents were able to release metals from the more immobile soil fractions, especially if the amount of easily soluble metals was comparatively small. To answer this question the sequential extraction was modified by carrying out selected weak extraction steps several times. As expected the intensified extraction conditions caused a decrease of the element content within the more resistant phases. However, the additional release in the first four extraction steps of Pb, Mn, Fe, and Zn was only in the range of 5 to 10%. Furthermore, it was observed that a single EDTA extraction (step four within the sequential extraction scheme) was capable to extract the same amount of metals as the first four extraction steps of the original scheme at a variation of about 15%. From these results it was concluded that the EDTA step alone already represents a reliable pool of mobilisable metals. Thus it can be maintained that such a simple single EDTA extraction can be used to assess the environmental risk from heavy metal contaminated soils or to predict the potential heavy metal release of soil remediation processes. 相似文献
73.
Heavy metal polluted sites are bearing an acute hazardous risk for the groundwater, but also a potential one. While the acute risk can be assessed directly via seepage water measurements, determination of the potential risk is much more complex. It results from the sum of all reactions that are capable to mobilize heavy metals under worst case environ-mental conditions. Using a fourfold sequential extraction (SE4) such a worst case was simulated for four soils highly contaminated with Pb, Zn, and Cu. The resulting potential mobilizable amounts ϕpm have been compared with those derived from 6 single extractions. By means of variance analyses, it is shown that ϕpm of lead can be represented by a single extraction with NH2OH. In contrary, ϕpm of zinc can be represented using the pHstat test or an extraction with aqua regia, while ϕpm of copper can be represented only by aqua regia extraction. The water-soluble amounts deriving from the DEV-S4 test do not correlate with the potential mobilizable amounts of any metal. Therefore, an assessment of contaminated sites should include an aqua regia extraction additionally to the seepage water analysis. 相似文献
74.
75.
采用稀碱浸提、蛋白酶水解与三氯乙酸沉淀相结合脱蛋白的工艺,对杂交鲟软骨提取琉酸软骨素的方法进行了较系统的研究。综合考察各种影响因素,设计了正交试验对提取工艺参数进行了优化,并对产品的质量指标进行了检验。结果表明,最佳提取工艺参数为:碱提取时料液比为1:2.0,碱浓度为4%,碱提温度为40℃;胰蛋白酶的酶解温度为55℃,酶量为2%,酶解时间为10h,制备的硫酸软骨素为白色粉末,得率为28.9%,纯度为92.3%,蛋白质含量为2.59%,各项质量指标完全符合标准要求。与目前已报道的其他软骨素制备工艺相比较,该方法具有工艺简便,提取率高,产品纯度高的特点。光谱分析法结构鉴定结果表明它是一种软骨素肽,其主要成分为硫酸软骨素C。 相似文献
76.
本文通过恒界面池法研究了以4’—乙酰基苯并—15—冠—5作为萃取剂和1—丁基—3—甲基咪唑双[(三氟甲基)磺酰基]酰亚胺作为协萃剂的萃取体系从高浓度水溶液中提取锂的动力学。研究了搅拌速度、平衡时间、温度、界面面积和传质阻力区对锂离子传质速率的影响。结果表明,界面膜的厚度在1 600 rpm~2 000 rpm 转速范围内是逐渐变薄的,并且在1 800 rmp~2 000 rmp转速范围内是没有变化的,说明锂离子传质速率1 800 rmp~2 000 rmp转速范围内是不变的;在锂离子的萃取平衡时间为40 min;萃取过程的传质阻力主要来自有机相;该萃取过程是混合控制的动力学过程;在两相界面上发生的萃取反应。通过研究锂离子、冠醚离子液体的浓度,锂离子的动力学方程可表达为:νLi,0=10-3.843±0.001·[Li+]0.907 1·[+] 0.832 8·[AcB15C5] 0.855 5。通过两相界面处形成锂离子最终配合物的传质速率步骤推导出锂的提取机理,这与实验结果一致。 相似文献
77.
在气相色谱-质谱分析中,负化学电离源质谱特别适合于高电负性目标物的分析,但不同反应气的对比研究工作至今未见报道。本研究采用甲烷、异丁烷、氨气、甲烷+氨气混合气、异丁烷+氨气混合气作为反应气,在负化学离子源内对电负性较高的有机磷农药进行电离实验,对反应气压力、离子源温度、灯丝发射电流等多项参数进行了考察。结果表明:采用纯氨气作为反应气,检测背景低,质谱真空负荷小,并可在负化学源质谱上获得最高的灵敏度。配合加速溶剂萃取方法,对土壤中的有机磷农药残留进行分析,方法全流程回收率为73.3%~108.1%,精密度为2.5%~8.8%,检出限为0.01~0.32μg/kg,各项指标均可满足实际样品测试需求。 相似文献
78.
《Chemie der Erde / Geochemistry》2014,74(4):615-623
Heavy metals having both natural and anthropogenic origin are common contaminants in soils and sediments, and can be transferred and bioaccumulated at all levels of the food chain, posing serious environmental concern to the local population. In this paper, agricultural soils from the Province of Ferrara (easternmost part of the Padanian Plain, northern Italy) were investigated to assess the levels of potentially toxic metals in relation to their phytoavailability. Agricultural soils have been sampled in order to identify the origin, mobility and bioavailability of heavy metals, collecting superficial and deeper (depths of 20–30 and 100–120 cm, respectively) horizons. The “total” XRF analyses properly elaborated with a statistical approach reveal that soils evolved from two distinct types of alluvial sediments, in turn related to the Po and Reno rivers; the former type is distinctively enriched in heavy metals (particularly Cr and Ni), reflecting the presence of femic and ultrafemic rocks in the hydrological basin of River Po. The absence of Top Enrichment Factors for Ni, Co, Cr, V, and Pb suggests that the content of these elements is natural and unaffected by contamination, whereas superficial enrichments of Cu (and Zn) is ascribed to anthropogenic inputs related to agricultural activities. Multiple extraction tests using variously aggressive reactants (aqua regia, DTPA, EDTA, NH4NO3, and H2O) analyzed by ICP gave insights on the specific mobility of the distinct elements, which decreases in the following order: Pb > Cu > Cd > Co > >Ni > Cr. Taking into consideration the elements that are inducing the main concerns, Cr appears scarcely mobile, whereas Ni could be more phytoavailable and has to be monitored in the local agricultural products. Cd although scarcely abundant has to be monitored for its mobility and toxicity, whereas Cu although abundant and extremely mobile doesn’t induce concerns as it is not hazardous for the living receptors. 相似文献
79.
正Cesium as a kind of alkali metals has widely been used in catalysis,medicine,biology,magnetic fluid power and other high-tech fields(Liao and Yang,2012;Cao et al.,2011;Wang et al.,2011).Although there was abundant of 相似文献
80.
石煤是一种可综合利用的矿产资源,提取石煤中钒、钼、镍等金属是其综合利用之一.石煤在发电燃烧过程中钒的物相发生显著变化,而钒物相的变化对钒的可浸出性产生较大的影响.笔者采用选择性连续提取方法对四川某地石煤原矿和石煤飞灰进行分析研究,发现石煤原矿中钒主要存在于硅铝酸盐相和有机质相中,部分存在于铁锰氧化物相及吸附态中,极少部分存在于碳酸盐相中.而石煤发电飞灰中钒主要存在于有机质相、硅铝酸盐相和铁锰氧化物相中,少量的钒以吸附态形式赋存.燃烧过程中石煤的各种含钒矿物发生离解,其中的钒得到释放并被氧化成高价态.高价钒一部分与Na、Cl等结合生成可溶性化合物,形成吸附态的钒;另一部分与Fe、Na、Ca等发生反应生成难溶性化合物,并以一定形式富集在飞灰的有机质相、硅铝酸盐相和铁锰氧化物相中. 相似文献